Turning-tool.



3.4T. B. RHEINPELDT.

TURNING TOOL.

APPLICATION FILED AUG. 29, 1908.

931,889. Patented Aug. 24, 1909.

w W HES-9E8 INVENTOR A TTOHIIEY.

ANDREW. a cmum can PNOTO-LTIHOGRAPHERS wnsummnu D c JOHN T. B. RHEINF-ELDT, 0F PHILADELPHIA, PENNSYLVANIA.

TURNING-TOOL.

Specification of Letters Patent.

Application filed August 29, 1908.

Patented Aug. 24., 1909.

Serial No. 450,892.

To all whom it may concern:

Be it known that I, JOHN T. B. RHEIN- FELDT, a citizen of the United States, residing in the city and county of Philadelphia, in the State of Pennsylvania, have invented a certain new and useful Improvement in Turning-Tools, of which the following is a throughout the cutting operation, will operate without chattering even when the tool is provided with an extended cutting edge, and will be well adapted to resist the stresses encountered in operation.

A-further object of the invention is to provide a simple compact and reliable mechanismlfor attaining the objects first enumeratec.

In the form of carrying out the invention disclosed, I have accomplished the various objects sought by the form which I have given to the tool and by the mechanism which I have provided for feeding the tool into the work. The tool shown is in the form of a segmental arc, and I have provided simple and effective .mechanism for rotating the tool to feed it into the .work about an axis so located that each point in the cutting edge may travel in an arcconcave toward the center line of the work and having a radius of curvature greater than the radius of theportion of the work finished by'said cuttingpoint, and have so arranged the tool and its supporting mechanism that the work may be brought into the position in which it is traversed by the axis of movement of the tool, so that the distance'between-the center line of the work and the axis of movement of the tool isless than the radial distance betweentheaxis of movement and the cutting edge. In the tool shown, the-extended cutting edge of the tool is generally oblique to the axisaboutwhich the toolis turned.

The various features of novelty which characterize my invention are-pointed out with particularity in theclaims annexed to and forming a part of this specification. For

- line 22 of Fig. 1.

however, and the advantages possessed by it, reference may be had to the accompanying drawings and descriptive matter in which I have illustrated and described one of the forms in which the invention may be embodied.

Of the drawings: Figure 1 is a side elevation of the tool and feeding mechanism therefor. Fig. 2 is a section taken on the Fig. 8 is a perspective view of the tool shown in Figs. 1 and 2; and Fig. 4 is an elevation of a portion of the Work which may be formed by the tool shown in Figs. 1, 2 and 3. i

In the form of the invention shown in the drawings, A represents the turning tool for turning the rotating work E, and B the holder for the tool. 1

The tool A comprises a body portion" A and a guide rib A having grooves or guideways A formed in its edges. The body A and rib A as well as the grooves A are in the form of segmental arcs, the common axis of curvature of which is indicated in Fig. 1 by the point A represents the chip engaging'face of the too V The rib A is provided on its periphery with gear teeth A.

The holder Bin the form shown comprises two parts B and B clamped together by bolts B The holder B is provided with a recess receiving the rib A and with curved guides or ribs B which enter the rooves A and also with a chamber in'wIiich is mounted a spur gear C meshing with the gear teeth A. The spur gear is secured to a spindle C j ournaled in the holder B and provided with an 0 erating handle C by means ofwhich the too maybe turned in the holder about the axis A.

The holder B is stationary during any given turning operation and may be mounted on any suitable support, as the turret of a turret lathe or the tool carriage of an ordinary lathe. In the form shown, the holder is provided with an extension B adapted to be clam ed to a tool carriage or other support D y bolts D passing through slots B in the extension B. When these boltsD are loosened, the support may be moved bodily toward and away from the .work E by an adjusting screw D which is journaled in the support D and is threaded through a threaded lug B formed on the under side of a better :understanding of the invention, lthe extension It is to be understood,

In Fig. 1, the point E represents the axis.

of the work E and the work center line of the lathe as well, and E and E the rough and finished peripheries of the portion of the work acted on by the point A of the cutting edge of the tool. The are X Y Z represents the path of the point A as the tool is turning about the axis A and it will be observed that a the arc X Y Z intersects the periphery E at case, the inner surface of the tool is not a the point X, and touches the periphery IE only at the point Y, where the line connecting the points A and E cuts the periphery E The are X Y Z, if extended, would intersect the periphery E at a point on the other side of the point Y from the point X and at a distance from the point Y equal to the distance between points Y and X. It is clear from the drawings that the arc X Y Z must not only have its concave side toward the work but must have a radius of curvature greater than the radius of the circle E In practice, in order to have the tool roperly clear the work, I prefer to make the c istance A E slightly greater than the difierence between the radii of the circles E and E or rather I make it slightly greater than the maximum depth of out which it is desired to take with the tool.

By making the cutting edge not parallel but oblique to the axis A, I insure that different points, A A A etc. in the cutting edge shall commence and complete their cutting movements at difierent times and this is highly advantageous in preventing chattering of the tool and in avoiding injurious strains. At the same time, the operation of grinding the tool is a comparatively simple one even though, as is usually the simple cylinder but is formed with ribs and grooves in order to produce work of the character shown in Fig. 4.

1 By making the tool are shaped and of an internal diameter not much greater than the rough diameter of the Work to be operated on, I obtain a tool which is strong and well adapted to resist the strains of the cutting operation.

A material advantage of the feed de- 7 scribed is that the cutting angle, t. e. the

' angle between the line A and the tangent to the Work at any cutting point as A changes only slightly during the entire cutting opera? tion of such. It will be understood that this that thesmaller the distance between the points A and E, the less is the change in cutting angle produced as the cutting edge moves through the quadrant between X and Y. I prefer, however, to make the distance A Ev a little greater than the maximum depth ofcut which it is desired to take with 'the tool, since in practice the change in cutting angle is always relatively small with the character of feed described, where the dis-- tance between points A and Eis always substantially less than the radius of curvature of the path of the cutting edge. By making the distance A E? a trifle greater than the maximum depth of out which it is desired to take with the tool, a compact tool and feeding mechanism is had, while at the same time a proper clearance is obtained with a tool of a shape well adapted to resist the strains of the cutting operation.

Having now describedmy invention, what I claim as new and desire ,to secure by Letters Patent is: V t

1. A turning tool, in the form of a segmental arc, having its ends spaced-apart,

and having its cutting edge at the intersection of its inner curved surface with'one end surface of the are, said end surface extending obliquely of the arc and serving as the chip.

engaging surface of the tool.

2. A turning tool, in the form of a seg-' mental arc, having its ends spaced apart,

and having its inner curved surface grooved to give an irregular contour to the work operated upon, and having its. cutting edge at the intersection of said inner curved surface withoneend surface of the arc, said end surface. extending obliquely to the axis 'of g V curvature of the arc and serving asthe chip engaging surface of the tool.

r v 3. The combination with a turning tool, of a holder therefor, said tool and holder being provided with coacting devices whereg p by the tool'may be'fed into the work by turning the tool relative to the holder to carry the cutting edge of the tool through a circular ath so located relative to the contour of the holder and the tool that the'work being acted upon by the tool may extend into a position in which it is traversed by the axis of said circular path; is V a. The combinatlon with a turning tool, of a holder therefor, said toolland holder being provided with coacting curved guides T and guide ways whereby the tool may be fed into the Work by moving the'tool relative to the holder to carry the cutting edge of the tool through a circular path so located 7 relative to the contour of the holder and the tool that the work being acted upon by the tool may extend into a position in which it is traversed by the. axis ofsaid circular path, and means for moving the tool relative to the' holder.

5. The combination with a turning tool,

of a holder therefor, said tool and holder being provided with coacting devices whereby the tool may be fed into the work by turning the tool relative to the holder to carry the cutting edge of the tool through a circular path, said tool being concaved toward the axis of said circular path, and the latter being so located relative to the contour of the holder that the work being acted upon may extend into a position in which it is traversed by the axis of said circular path.

6. The combination with a turning tool, provided with a gear segment, of a holder for the tool, said tool and holder being provided with coacting devices whereby the tool may be fed into the work by turning the tool relative to the holder to carry the cutting edge of the tool through a circular path so located relative to the contour of the holder and the tool that the work being acted upon by the tool may extend into a position inwhich it is traversed by the axis of said circular path, a gear mounted in the holder and meshing with the gear segment, and means for rotating said gear to turn the tool relative to the holder.

7. The combination with an arc shaped turning tool, of a holder therefor, said tool and holder being provided with coacting devices whereby the tool may be fed into the work by turning the tool relative to the holder to carry the cutting edge of the tool through a circular path about an axis substantially coincident with the axis of curvature of the tool and so located relative to the contour of the holder that the work being acted upon by the tool may extend into the concavity of the tool and into a position in which it is traversed by the axis of said circular path.

8. The combination with the tool support of a lathe, of a tool connected to said support and adapted to swing relatively thereto about an axis located at a distance from the work center line of the lathe, said distance being substantially less, however, than the distance between said axis and the cutting edge of the tool.

9. The combination with the tool support of a lathe, of a tool holder mounted thereon and adjustable toward and away from the work center line of the lathe, a tool mounted in said holder to move relatively thereto about an axis parallel to the work center line of the lathe and separated from said center line by a distance, said distance being substantially less, however, than the distance betweensaid axis and the cutting edge of the tool.

JOHN T. B. RHEINFELDT.

Witnesses ARNOLD KATZ, D. STEWART. 

